No, I think I got the names wrong. Arggggh!!! （/TДT)/
It was implied in their spin-off doujin that Kan-chan and Yumi switched, so they were both top and bottoms :)
Whatever with the names but, kyaaaaaa! I really liked the idea when a couple switch roles in bed! ε=ε=(ノ≧∇≦)ノ
Dun' know if I crossed path with that DJ tho.
very late reply but it's called Azami!
http://www.mangago.zone/read-manga/azami/
I think there was a scene where we clearly saw Kan-chan was bottom when he was still with Yumi but I might have mistaken it with a scene in his workplace :((
But I'm pretty sure they did have some little bickering about who gets to put it inside haha! And yess for switch couples! And power bottoms!
Yumi became so slutty in this series and became a power bottom when he's ripping Kan-chan's ass in the past. Or... is it the other way around? Is Yumi the uke too when he and Kan-chan we're together? Ugggh! (￣∇￣")